A car has broken down in the outside lane – which is causing problems for drivers heading towards Ipswich and Bury St Edmunds.
Police were called to the scene, close to the Shell garage, at around 4.15pm and are now in the process of moving it onto the hard shoulder.
Drivers are being warned they could face delays of up to seven minutes while recovery of the vehicle, thought to be a Mazda, from the carriageway.
According to the AA Traffic News website, motorists are experiencing delays of up to ten minutes and the average speed is 25mph.
The car broke down between junction 57, the Nacton Interchange and junction 56, Wherstead.
Traffic is expected to clear over the next 30 minutes but delays could run into rush hour, a police spokeswoman said.
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